Genome-wide high-resolution screening in Dupuytren's disease reveals common regions of DNA copy number alterations.

PURPOSE: Dupuytren's disease (DD) is a familial disorder with a high genetic susceptibility in white people; however, its etiopathogenesis remains unknown. Previous comparative genomic hybridization studies using lower-resolution, 44-k oligonucleotide-based arrays revealed no copy number variation (CNV) changes in DD. In this study, we used a higher-resolution genome-wide screening (next-generation microarrays) comprising 963,331 human sequences (3 kb spacing between probes) for whole genome DNA variation analysis. The objective was to detect cryptic chromosomal imbalances in DD. METHODS: Agilent SurePrint G3 microarrays, one million format (Agilent Technologies, Santa Clara, CA), were used to detect CNV regions (CNVRs) in DNA extracted from nodules of 4 white men with DD (age, 69 +/- 4 y). Reference samples were from the DNA of 10 men who served as control patients. Copy number variations that were common to greater than 3 assessed DD individuals (p < .05) were selected as candidate loci for DD etiology. In addition, quantitative polymerase chain reactions (qPCR) assays were designed for selected CNVRs on DNA from 13 DD patients and 11 control patients. Independent t-tests and Fisher's exact tests were carried out for statistical analysis. RESULTS: Three novel CNVs previously unreported in the phenotypically normal population were detected in 3 DD cases, located at 10q22, 16p12.1, and 17p12. Nine polymorphic CNVRs potentially associated with DD were determined using our strategic selection criteria, locating to chromosomes 1q31, 6p21, 7p14, 8p11, 12p13, 14q11, 17q21 and 20p13. More than 3 of the DD cases tested had a CNVR located to a small region on 6p21 and 4 CNVRs within 6p21-22 of the human leukocyte antigen (HLA) genes. CONCLUSIONS: Three novel copy number alterations were observed in 3 unrelated patients with sporadic (no known family history) DD. Nine polymorphic CNVRs were found to be common among the DD cases. These variants might contain genes involved in DD formation, indicating that important gene networks expressed within the palmar fascia might contribute to genetic susceptibility of DD.

A technique for accurate and safe injection of steroid in trigger digits using ultrasound guidance.

Steroid injections have long been the main stay of conservative treatment of trigger digits. This procedure gives variable results, which is dependent on a number of factors. The injection of the steroid in the right place improves the success rate and also prevents complications associated with the procedure. We describe a technique using ultrasound for accurate injection of steroid to maximise its beneficial effects in treatment of trigger digits.

Identification of a novel mitochondrial mutation in Dupuytren's disease using multiplex DHPLC.

Dupuytren's disease is a familial fibroproliferative disorder of late onset affecting the hands. It is extremely common in individuals of Northern European extraction. Genetic studies have yet to identify the genes involved in the formation of the disease. Mitochondria play a critical role in cell metabolism and apoptosis. It is known that defective mitochondria generate abnormally high levels of reactive oxygen species by means of electron leak and that antioxidant enzyme activities decrease with age in skin fibroblasts. Respiratory function of mitochondria is also impaired in aging human tissues. Oxidative stress and production of free radicals may be important factors in the pathogenesis of Dupuytren's disease. Mitochondrial genes are also included in the regulation of apoptosis. Diseased tissue contains large numbers of myo- fibroblasts, which disappear by apoptosis during normal wound healing. High numbers of mitochondria have been observed in fibroblasts derived from diseased tissue. In the light of this evidence, the mitochondrial genome represents a potential location for candidate susceptibility genes for this late-onset disorder. In this study, the authors investigated the presence of mutations within the mitochondrial genome in 40 subjects; 20 Caucasian Dupuytren's disease patients with a maternally transmitted inheritance pattern and 20 control subjects were matched for age, sex, and race using a multiplex denaturing high-performance liquid chromatography approach. A hitherto unknown heteroplasmic mutation located within the mitochondrial 16s rRNA region was evident in 90 percent of patients and absent from all control subjects (p < 0.001; chi2 = 16.1). This mutation may be important in the pathogenesis of Dupuytren's disease.

Improved tumour localisation using indium-111 labelled antibodies.

Immunoglobulin G (IgG) antibodies to carcinoembryonic antigen (CEA) were labelled with radioactive indium (111In) or iodine (131I) and a comparison made of their value in locating CEA producing tumours. Eleven patients given 111In-anti-CEA had 31 tumours as judged by a combination of all techniques. Of these, 28 were detected by 111In-anti-CEA and 26 by conventional clinical techniques. Five of the patients also received 131I-anti-CEA. These patients had 15 tumour areas. Thirteen were detected by 111In and eight by 131I. 111In also produced a better signal to noise ratio in the scans and thereby showed lesions with greater certainty. In addition, the 111In isotope continued to accumulate in the tumour areas for considerably longer than 131I. Absorbed doses (whole body) were similar for both isotopes. The results show that antibody scanning is greatly improved by using 111In as the radiolabel in place of 131I and should allow the detection of smaller or deeper lesions.

Detection of thyroid tumours using radio-labelled anti-thyroglobulin.

IgG antibody to human thyroglobulin was labelled with 131Iodine (131I) and used to locate deposits of thyroid follicular and papillary tumours with a gamma camera. Of twelve patients studied a total of 40 tumour 'areas' were detected by a variety of clinical and radiological techniques. Sixteen of these were detected using conventional 131I uptake scans whereas 34 were positive on the antibody scans. The difficulty of assessing diffuse pulmonary lesions (3 areas) and the possibility that free 131I from labelled antibody may have contributed to the antibody scan results in six areas left 31 definite areas for scan comparison. Twenty seven (87%) areas were positive on the antibody scan, nine (29%) were positive on conventional 131I scans whilst 24 (77%) areas were detected by a combination of clinical and other radiological criteria. Five areas were positive on the antibody scan alone but there was evidence, albeit indefinite, that these areas contained tumour. Four of the 31 areas were not detected by the antibody scans. The results indicate that anti-thyroglobulin scanning is more sensitive than conventional 131I-iodide scans and may contribute to the staging and management of thyroid cancer.